Cancer is a disease marked by the uncontrolled growth of abnormal cells. Cancer cells have overcome the barriers imposed on normal cells, which have a finite lifespan, to grow indefinitely. As cancerous cell growth continues, genetic alterations may mount until a cancerous cell has achieved a more aggressive growth phenotype. If left untreated, metastasis, which is the spread of cancer cells to distant areas of the body by way of the lymph system or bloodstream, may ensue. Metastasis can result in the destruction of healthy organs and tissues when cancerous cells infiltrate different areas of the body and continue growing to form new tumors.
According to a recent American Cancer Society study, approximately 1,437,180 new cancer cases are expected to be diagnosed in the United States in the year 2008 alone. Despite the availability of numerous chemotherapeutic agents and diagnostic tools, additional diagnostic methods are needed to investigate the mechanisms and pathways that lead to cancerous cell growth. Such methods may lead to the discovery of new drugs that can be used effectively against various types of cancers.